- 8x 16-bit TTL-compatible I2C I/O expanders (totaling 128 bits I/O)
- USB to I2C adapter
- Donor MMC5A chip from 'Just Breed', removed successfully
- 0.65mm pitch QFP-100 20x30 breakout board, MMC5A mounted on it successfully
- All connections from I/O expanders to MMC5 complete (except audio)
- Preliminary C# GUI on computer to create automated tests, to let it run overnight, etc.
The first auto-test that I want to create is to try reading from all possible CPU addresses, recording whether the MMC5 is open bus or reporting a value. If it is a value, recording the value. This will tell us each and every address to which the MMC5A responds, and nail down that aspect for the memory map. I will get this test working first, then we can think about what to do next. I would like to start reading and writing to PRG-RAM and watching the unknown lines in the not-too-distant future. I am pretty sure we will be OK on noise and wire length because I will be controlling the M2 line manually with the I/O expanders. This will definitely be a very slow-mo test process.
My goal is to work on the GUI this weekend and see if I can get some sort of test running. Will report progress!